Unfortunately, there is not option to edit a milestone information currenly. However, when you click "Pay", you should be able to edit the amount you would like to release to the freelancer. In that way you can release parts of the funded amount as the freelancer completes the tasks. I hope this information helps and let us know if you have any further questions.
My Buyer failed to send me the website credentials within the deadline for development a site. He wanted to extend the deadline. But there is no option to change (extend) the Milestone deadline from the Buyer account.
For this case, If my Buyer wanted to end the current contract, would it make any bad effect (bad reputation, bad success score, account hold, etc.) for my Freelancing profile?
Please help me. I am very worried about it.
Milestone delivery dates are optional and do not have any effect on your profile/account/reputation.
Note that there are other factors that do affect you Job Success Score, so make sure to communicate with your client regarding the future of this job, and discuss the terms and project scope before you accept a job offer going forward.
There are two things you could do. You could either end the job and then make a new offer to the freelancer with the correct amount in Escrow. Alternatively, you can leave it as it is for now and when the assignment is completed, you can release a partial amount and request for the rest to be refunded back to you.